src/HOL/UNITY/WFair.thy
changeset 4776 1f9362e769c1
child 5155 21177b8a4d7f
     1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/src/HOL/UNITY/WFair.thy	Fri Apr 03 12:34:33 1998 +0200
     1.3 @@ -0,0 +1,43 @@
     1.4 +(*  Title:      HOL/UNITY/WFair
     1.5 +    ID:         $Id$
     1.6 +    Author:     Lawrence C Paulson, Cambridge University Computer Laboratory
     1.7 +    Copyright   1998  University of Cambridge
     1.8 +
     1.9 +Weak Fairness versions of transient, ensures, leadsTo.
    1.10 +
    1.11 +From Misra, "A Logic for Concurrent Programming", 1994
    1.12 +*)
    1.13 +
    1.14 +WFair = Traces + Vimage +
    1.15 +
    1.16 +constdefs
    1.17 +
    1.18 +  transient :: "[('a * 'a)set set, 'a set] => bool"
    1.19 +    "transient Acts A == EX act:Acts. A <= Domain act & act^^A <= Compl A"
    1.20 +
    1.21 +  ensures :: "[('a * 'a)set set, 'a set, 'a set] => bool"
    1.22 +    "ensures Acts A B == constrains Acts (A-B) (A Un B) & transient Acts (A-B)"
    1.23 +
    1.24 +consts leadsTo :: "[('a * 'a)set set, 'a set, 'a set] => bool"
    1.25 +       leadsto :: "[('a * 'a)set set] => ('a set * 'a set) set"
    1.26 +  
    1.27 +translations
    1.28 +  "leadsTo Acts A B" == "(A,B) : leadsto Acts"
    1.29 +
    1.30 +inductive "leadsto Acts"
    1.31 +  intrs 
    1.32 +
    1.33 +    Basis  "ensures Acts A B ==> leadsTo Acts A B"
    1.34 +
    1.35 +    Trans  "[| leadsTo Acts A B;  leadsTo Acts B C |]
    1.36 +	   ==> leadsTo Acts A C"
    1.37 +
    1.38 +    Union  "(UN A:S. {(A,B)}) : Pow (leadsto Acts)
    1.39 +	   ==> leadsTo Acts (Union S) B"
    1.40 +
    1.41 +  monos "[Pow_mono]"
    1.42 +
    1.43 +constdefs wlt :: "[('a * 'a)set set, 'a set] => 'a set"
    1.44 +  "wlt Acts B == Union {A. leadsTo Acts A B}"
    1.45 +
    1.46 +end